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CN-121983709-A - Multifunctional assembly for safe operation and disaster prevention and control of lithium ion battery

CN121983709ACN 121983709 ACN121983709 ACN 121983709ACN-121983709-A

Abstract

The invention provides a multifunctional component for safe operation and disaster prevention and control of a lithium ion battery, and belongs to the technical field of lithium ion batteries. The polyimide film comprises a substrate layer, a functional layer and a packaging layer, wherein the substrate layer comprises a substrate, polyimide is uniformly grown on the surface of the substrate in situ by adopting an in situ generation mode, and a polyimide film is formed. The functional layer comprises heating wires and sensors, the heating wires and the sensors are arranged on one side or two sides of the substrate layer in a staggered mode in space projection, the heating wires and the sensors are not interfered with each other, and the upper surface of the functional layer forms a packaging layer. The invention takes the heat-insulating flame-retardant material as a matrix, so that the component has better heat-insulating and flame-retardant properties, and can provide buffering for adjacent batteries when the batteries are out of control. The flexible in-situ integrated heating wire and the multifunctional sensing layer are adopted to realize low-temperature preheating and signal sensing of the battery in a stress-free mode, so that the safe operation and disaster prevention and control capability of the battery are effectively improved.

Inventors

  • XIE SONG
  • Shu Yingrong
  • XU YI

Assignees

  • 中国民用航空飞行学院

Dates

Publication Date
20260505
Application Date
20260112

Claims (7)

  1. 1. The multifunctional component for safe operation and disaster prevention and control of the lithium ion battery is characterized by comprising a basal layer, a functional layer and a packaging layer; the substrate layer comprises a substrate (1), wherein the substrate (1) is an aerogel felt, polyimide uniformly grows on the surface of the substrate (1) in situ in an in-situ generation mode on the surface of the substrate (1), and a polyimide film (6) is formed on the surface of the aerogel felt; the functional layer comprises heating wires (2) and sensors (3), and the heating wires and the sensors are arranged on one side or two sides of the basal layer in a staggered manner on space projection, so that the heating wires and the sensors are not mutually interfered; the upper surface of the functional layer forms an encapsulation layer (7).
  2. 2. The multifunctional module for safe operation and disaster prevention and control of a lithium ion battery according to claim 1, wherein the density of the aerogel blanket is 0.12-0.18 g cm "3.
  3. 3. The multifunctional assembly for safe operation and disaster prevention and control of a lithium ion battery according to claim 1, wherein the preparation method of the polyimide film (6) is as follows: Firstly, preprocessing an aerogel felt of a matrix (1), placing the aerogel felt in 80 ℃ for drying in vacuum for 2 hours, and storing the aerogel felt in a dryer for standby after the aerogel felt is cooled to room temperature; Secondly, preparing a surface treatment liquid, namely dissolving 3-aminopropyl triethoxysilane into an absolute ethyl alcohol/water mixed solution with the volume ratio of 95/5 according to 0.5vol%, and using glacial acetic acid to adjust the pH value to 5; Immediately after taking out, the subsequent polyamic acid coating is carried out, the polyamic acid solution with the solid content of 30-70 percent is selected, a doctor blade coating method is adopted, the scraping gap is 80-120 mu m, and then the stage curing is carried out in the air atmosphere, wherein the temperature is 80 ℃,30-60min,120 ℃,45-60min,180 ℃,60-90min,230 ℃,90-120min and 260-280 ℃ for 30-60min.
  4. 4. The multifunctional assembly for safe operation and disaster prevention and control of a lithium ion battery according to claim 3, wherein the polyamic acid structure comprises: The dianhydrides are respectively pyromellitic dianhydride, 3', 4' -biphenyl tetracarboxylic dianhydride, 4 '-oxydiphthalic dianhydride and 3,3', one of 4,4 '-benzophenone tetracarboxylic dianhydride, 4' - (hexafluoroisopropyl) diphthalic dianhydride, 4'- (4, 4' -isopropyl diphenoxy) bis (phthalic anhydride); The diamine is one of 4,4' -diaminodiphenyl ether, 3,4' -diaminodiphenyl ether, p-phenylenediamine, m-phenylenediamine, 4' -diaminodiphenyl methane, 1, 3-bis (4-aminophenoxy) benzene, 2-bis [4- (4-aminophenoxy) phenyl ] propane and bis (3-aminopropyl) end-capped polydimethylsiloxane respectively.
  5. 5. The multifunctional assembly for safe operation and disaster prevention and control of the lithium ion battery according to claim 1, wherein the heating wire (2) is formed on the surface of the basal layer by forming a resistance material with a heat generating effect on the surface of the basal layer in situ in a linear roundabout manner.
  6. 6. The multifunctional assembly for safe operation and disaster prevention and control of the lithium ion battery according to claim 1, wherein the sensor (3) is formed by forming a flexible temperature, pressure or gas sensitive material with a specific sensing function on the surface of the basal layer in situ.
  7. 7. The multifunctional module for safe operation and disaster prevention and control of lithium ion batteries according to claim 1, wherein the packaging layer (7) is formed into a complete plane by surface packaging and coating with polydimethylsiloxane, polyimide or polyethylene terephthalate.

Description

Multifunctional assembly for safe operation and disaster prevention and control of lithium ion battery Technical Field The invention provides a multifunctional component for safe operation and disaster prevention and control of a lithium ion battery, and belongs to the technical field of lithium ion batteries. Background Lithium ion batteries have become a common energy storage device because of their high energy density and long cycle life. However, its performance in low temperature environments can be significantly degraded and accompanied by thermal safety risks. The low temperature can increase the viscosity of the battery electrolyte, reduce the ionic conductivity, sharply increase the internal resistance and influence the power output, and the lithium dendrite growth is easy to be initiated during charging, the diaphragm is pierced, and the short circuit and even the thermal runaway are initiated. The effective low-temperature heating technology is important to ensure the safe operation of the battery in a wider temperature range. The prior art mainly includes internal heating and external heating. The internal heating is generated by the battery, so that the efficiency is high, but the battery structure is often required to be adjusted or the complex control is implemented, the performance and the service life of the battery can be influenced, and the technical threshold and the risk are high. External heating is to heat the surface of the battery through adding a heating element outside the battery, which is the main scheme at present, but the current external heating scheme has single function and uneven heating, and cannot be adjusted according to the state of the battery. Short plates are also known in the art for battery condition monitoring and safety protection. Most of monitoring adopts an external rigid sensor, is difficult to attach to the surface of a battery, and is easy to cause signal delay or failure under impact. Most of thermal protection materials adopted in thermal safety protection, such as heat insulation cotton, aerogel gaskets and the like, are passive protection, lack of cooperation with a thermal management system, and cannot be intervened in early thermal runaway. In addition, the swelling that occurs during battery cycling often fails to release effectively, exacerbating battery aging and affecting battery life. Although the development of flexible electronic technology brings new possibility for heat management, most of the existing flexible elements are single in function, and the functions of heating, multi-parameter sensing, heat insulation, flame retardance, stress buffering and the like cannot be integrated, so that the comprehensive requirements of complex working conditions in actual application scenes cannot be met. Disclosure of Invention Aiming at the technical problems, the invention provides a highly integrated, structurally stable and functionally coordinated component, which simultaneously realizes the following three core functions, thereby improving the performance and safety of the lithium ion battery under wider temperature range and complex working conditions: (1) Low temperature heating function. The battery is quickly and uniformly preheated through the low-power-consumption and high-efficiency heating loop, so that the problems of difficult battery starting, performance attenuation, lithium precipitation of a charging negative electrode and the like caused by low ambient temperature are fundamentally solved. (2) And a multi-parameter real-time safety monitoring function. The in-situ integrated flexible sensor is used for collecting and identifying various parameters such as temperature, pressure, gas and the like of the battery in real time, so that early identification and intervention of the battery safety risk are realized. (3) Disaster prevention and control functions. Through the base body (1) material and the packaging design with heat insulation, flame retardance and stress buffering characteristics, when the battery is in thermal runaway, the heat diffusion can be effectively delayed, the flame propagation can be restrained, and more time is striven for the safe disposal of the system. The invention provides a complete technical scheme that: a multifunctional component for safe operation and disaster prevention and control of a lithium ion battery comprises a basal layer, a functional layer and a packaging layer; The substrate layer comprises a substrate body, the substrate body is an aerogel felt, and the density of the aerogel felt is 0.12-0.18 g cm & lt-3 & gt. Polyimide is uniformly grown on the surface of the matrix in situ by adopting an in-situ generation mode, and a polyimide film is formed on the surface of the aerogel felt. The functional layer comprises heating wires and sensors, the heating wires and the sensors are arranged on one side or two sides of the substrate layer in a staggered mode in space projection, the heating wires